Application layer FEC framework for WiGig

Abstract

A method and apparatus perform forward error correction in a wireless communication device in a wireless communication network. Application layer forward error correction (AL-FEC) capability information is transmitted during a capabilities exchange. A set of source packets are reshaped to k equal-sized source symbols. Systematic packets for the source symbols and at least one parity packet is encoded using a single parity check (SPC) AL-FEC code on the k source symbols. A header of each encoded packet includes a parity packet indicator. The encoded packets are processed in a media access control (MAC) layer and a physical (PHY) layer for transmission.

What is claimed is: 
     
       1. A method of performing forward error correction (FEC) in a wireless communication device in a wireless communication network, the method comprising:
 transmitting application layer forward error correction (AL-FEC) capability information during a capabilities exchange; 
 applying a single parity check (SPC) AL-FEC code on a set of k source packets to encode i) systematic packets for the set of k source packets and ii) at least one parity packet, a header of each of the encoded systematic packets and at least one parity packet comprising a parity packet indicator, wherein applying the SPC AL-FEC code to encode the at least one parity packet comprises computing a payload for the at least one parity packet by performing a bit-wise XOR on one of the set of k source packets; and 
 processing the encoded systematic packets and the at least one parity packet in a media access control (MAC) layer and a physical (PHY) layer for transmission; 
 wherein the SPC AL-FEC code comprises a non-interleaved mode, wherein encoding the systematic packets and the at least one parity packet comprises: 
 generating a sequence number i for one parity packet; 
 generating sequence numbers i+1, i+2, . . . , i+k for the set of k source packets; and 
 wherein computing the payload for the at least one parity packet comprises performing the bit-wise XOR on the set of k source packets to compute the payload for the parity packet with the sequence number i, 
 wherein the sequence number for the parity packet is included in a header for the parity packet, and the sequence numbers for the set of k source packets are included in headers for corresponding systematic packets. 
 
     
     
       2. The method of  claim 1 , wherein encoding the systematic packets for the set of k source packets and the at least one parity packet comprises performing a Hamming AL-FEC code in combination with the SPC AL-FEC code. 
     
     
       3. The method of  claim 1 , further comprising:
 receiving a packet block comprising at least one of systematic packets and repair packets; 
 determining whether at least one packet is missing in the received packet block; 
 when at least packet is missing, determining whether the received packets are AL-FEC encoded by checking the parity packet indicator in each received packet; 
 when the AL-FEC code is detected, determining whether the at least one missing packet may be recovered; and 
 in response to determining that the at least one missing packets may be recovered, performing AL-FEC decoding by using the received systematic and repair packets. 
 
     
     
       4. The method of  claim 3 , wherein determining whether the received packets are AL-FEC encoded further comprises determining whether the received packets are interleaved based on a number of parity packets received. 
     
     
       5. A method of performing forward error correction (FEC) in a wireless communication device in a wireless communication network, the method comprising:
 transmitting application layer forward error correction (AL-FEC) capability information during a capabilities exchange; 
 applying a single parity check (SPC) AL-FEC code on a set of k source packets to encode i) systematic packets for the set of k source packets and ii) at least one parity packet, a header of each of the encoded systematic packets and at least one parity packet comprising a parity packet indicator, wherein applying the SPC AL-FEC code to encode the at least one parity packet comprises computing a payload for the at least one parity packet by performing a bit-wise XOR on one of the set of k source packets; and 
 processing the encoded systematic packets and the at least one parity packet in a media access control (MAC) layer and a physical (PHY) layer for transmission; 
 wherein the SPC AL-FEC code comprises an interleaved mode with x subsets of source packets, wherein encoding the systematic packets and the at least one parity packet comprises: 
 generating sequence numbers i, i+1, i+2, f i+(x−I) for x parity packets, each parity packet corresponding to one of x subsets of source packets; 
 generating sequence numbers i+1, i+2, . . . , i+k for the set of k source packets; 
 interleaving the set of k source packets across the x subsets such that source packets with consecutive sequence numbers correspond to different subsets; and 
 wherein computing the payload for the at least one parity packet comprises computing a payload for each of the x parity packets by performing a bit-wise XOR on a corresponding subset of source packets, 
 wherein the sequence numbers for the parity packets are included in headers for corresponding parity packets, and the sequence numbers for the set of k source packets are included in headers for corresponding systematic packets. 
 
     
     
       6. The method of  claim 5 , further comprising:
 receiving a packet block comprising at least one of systematic packets and repair packets; 
 determining whether at least one packet is missing in the received packet block; 
 when at least packet is missing, determining whether the received packets are AL-FEC encoded by checking the parity packet indicator in each received packet; 
 when the AL-FEC code is detected, determining whether the at least one missing packet may be recovered; and 
 in response to determining that the at least one missing packets may be recovered, performing AL-FEC decoding by using the received systematic and repair packets. 
 
     
     
       7. The method of  claim 6 , wherein determining whether the received packets are AL-FEC encoded further comprises determining whether the received packets are interleaved based on a number of parity packets received. 
     
     
       8. An apparatus for performing forward error correction (FEC) in a wireless communication device in a wireless communication network, the apparatus comprising:
 a transmitter configured to communicate with other communication devices; and 
 a controller coupled to the transmitter and configured to: 
 control the transmitter to transmit application layer forward error correction (AL-FEC) capability information during a capabilities exchange; 
 apply a single parity check (SPC) AL-FEC code on a set of k source packets to encode i) systematic packets for the set of k source packets and ii) at least one parity packet, a header of each of the encoded systematic packets and the at least one parity packet comprising a parity packet indicator, wherein to apply the SPC AL-FEC code to encode the at least one parity packet the controller is configured to compute a payload for the at least one parity packet by performing a bit-wise XOR on one of the set of k source packets or a subset of source packets in the set of k source packets; and 
 process the encoded systematic packets and the at least one parity packet in a media access control (MAC) layer and a physical (PHY) layer for transmission; 
 wherein the SPC AL-FEC code comprises an non-interleaved mode, wherein the controller is further configured to: 
 generate a sequence number i for one parity packet; 
 generate sequence numbers i+1, i+2, . . . , i+k for the set of k source packets; and 
 wherein in computing the payload for the at least one parity packet the controller is further configured to perform the bit-wise XOR on the set of k source packets to compute the payload for the parity packet with the sequence number i, 
 wherein the sequence number for the parity packet is included in a header for the parity packet, and the sequence numbers for the set of k source packets are included in headers for corresponding systematic packets. 
 
     
     
       9. The apparatus of  claim 8 , wherein the controller is further configured to perform a Hamming AL-FEC code in combination with the SPC AL-FEC code when encoding the systematic packets for the set of k source packets and the at least one parity packet. 
     
     
       10. The apparatus of  claim 8 , wherein the controller is further configured to:
 receive at least one of systematic packets and repair packets; 
 determine whether at least one packet is missing; 
 when any packet is missing, determine whether the received packets are AL-FEC encoded by checking the parity packet indicator in each received packet; 
 when the AL-FEC code is detected, determine whether the at least one missing packet may be recovered; and 
 in response to determining that the missing packets may be recovered, perform AL-FEC decoding by using the received systematic and repair packets. 
 
     
     
       11. The apparatus of  claim 10 , wherein the controller is further configured to determine whether the received packets are interleaved based on a number of parity packets received when determining whether the received packets are AL-FEC encoded. 
     
     
       12. An apparatus for performing forward error correction (FEC) in a wireless communication device in a wireless communication network, the apparatus comprising:
 a transmitter configured to communicate with other communication devices; and 
 a controller coupled to the transmitter and configured to: 
 control the transmitter to transmit application layer forward error correction (AL-FEC) capability information during a capabilities exchange; 
 apply a single parity check (SPC) AL-FEC code on a set of k source packets to encode i) systematic packets for the set of k source packets and ii) at least one parity packet, a header of each of the encoded systematic packets and the at least one parity packet comprising a parity packet indicator, wherein to apply the SPC AL-FEC code to encode the at least one parity packet the controller is configured to compute a payload for the at least one parity packet by performing a bit-wise XOR on one of the set of k source packets or a subset of source packets in the set of k source packets; and 
 process the encoded systematic packets and the at least one parity packet in a media access control (MAC) layer and a physical (PHY) layer for transmission; 
 wherein the SPC AL-FEC code comprises an interleaved mode with x subsets of source packets, wherein the controller is further configured to: 
 generate sequence numbers i, i+1, i+2, . . . , i+(x−I) for x parity packets, each parity packet corresponding to one of x subsets of source packets; 
 generate sequence numbers i+1, i+2, . . . , i+k for the set of k source packets; 
 interleave the set of k source packets across the x subsets such that source packets with consecutive sequence numbers correspond to different subsets; and 
 wherein in computing the payload for the at least one parity packet the controller is further configured to compute a payload for each of the x parity packets by performing a bit-wise XOR on a corresponding subset of source packets, 
 wherein the sequence numbers for the parity packets are included in headers for corresponding parity packets, and the sequence numbers for the set of k source packets are included in headers for corresponding systematic packets. 
 
     
     
       13. The apparatus of  claim 12 , wherein the controller is further configured to:
 receive at least one of systematic packets and repair packets; 
 determine whether at least one packet is missing; 
 when any packet is missing, determine whether the received packets are AL-FEC encoded by checking the parity packet indicator in each received packet; 
 when the AL-FEC code is detected, determine whether the at least one missing packet may be recovered; and 
 in response to determining that the missing packets may be recovered, perform AL-FEC decoding by using the received systematic and repair packets. 
 
     
     
       14. The apparatus of  claim 13 , wherein the controller is further configured to determine whether the received packets are interleaved based on a number of parity packets received when determining whether the received packets are AL-FEC encoded.